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Temporal Rate Adaption-Evidence for Supramodal Timing Mechanisms?

时间速率适应——超模态计时机制的证据？

基本信息

批准号：
8712500
负责人：
SHINSUKE SHIMOJO
金额：
$ 20.81万
依托单位：
CALIFORNIA INSTITUTE OF TECHNOLOGY
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-09-01 至 2015-08-31
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): The long-term goal of this research is to understand the principles that govern crossmodal interactions in the temporal domain. The specific objective of this proposal is to identify and to characterize a supramodal timing mechanism for perception of rate. The central hypothesis is that there is a vigorous and adaptive central timing mechanism (responding to changes within the order of seconds to minutes) that is at least to some degree unified and amodal. The proposed studies will rely on a recently discovered crossmodal aftereffect in which repeated exposure to a pulsed adaptor stimulus leads to changes in the perception of the rate of pulsation of subsequent stimuli, such that a relatively fast adaptor lead to later stimuli being perceived as slower, while a relatively slow adaptor does the reverse. This happens even when the adaptor and test stimuli are presented with different modalities and are never presented together. In a series of psychophysical experiments, this effect will be tested with different configurations of unimodal, bimodal, and crossmodal visual stimuli. These experiments will measure the strength and direction of the aftereffect as it varies with different adaptor stimuli and with different spatial relationships and rate differences between adaptor and test. These experiments will provide for a strong test of the supramodal timing hypothesis. An additional set of psychophysical experiments will use continuous flash suppression to render participants are largely unaware of the visual stimuli and test whether adaptation still occurs. This will determine whether the effect requires conscious awareness (and thus may be largely cognitive) or is at least in part perceptual. A final set of experiments will use EEG to track the range of temporal frequencies and the perception threshold of the effect, via the study of the power spectrum and steady state frequency responses, and will provide an objective measure of the causal relationship between auditory and visual networks in creating the perceptual effect. The results of these experiments will place constraints on neuronal and computational models of temporal processing. Timing deficits have been linked to changes due to normal aging as well as to disorders including dyslexia, ADHD, Parkinson's disease, depression, and schizophrenia. A better model of how the brain encodes time has the potential to enhance understanding of these timing deficits and may have implications for potential clinical or psychological interventions.

描述（由申请人提供）：本研究的长期目标是了解支配时间域中跨模相互作用的原理。本提案的具体目标是确定和表征速率感知的超模定时机制。核心假设是，存在一种强有力的、自适应的中央计时机制（对秒到分钟的变化做出反应），至少在某种程度上是统一的和模态的。拟议的研究将依赖于最近发现的交叉模态后效，其中反复暴露于脉冲适配器刺激会导致对后续刺激脉动率的感知发生变化，例如相对较快的适配器会导致对后续刺激的感知变慢，而相对较慢的适配器则相反。即使适配器和测试刺激以不同的方式呈现，也不会同时呈现，这种情况也会发生。在一系列的心理物理实验中，这种效应将通过单峰、双峰和跨峰视觉刺激的不同配置来测试。这些实验将测量后效应的强度和方向，因为它随不同的适配器刺激以及适配器和测试之间的不同空间关系和速率差异而变化。这些实验将为超模定时假说提供有力的检验。另一组心理物理实验将使用持续的闪光抑制，使参与者在很大程度上不知道视觉刺激，并测试适应是否仍然发生。这将决定效果是否需要有意识的意识（因此可能主要是认知）或至少部分是感性的。最后一组实验将通过功率谱和稳态频率响应的研究，使用脑电图来跟踪该效应的时间频率范围和感知阈值，并将提供听觉和视觉网络在产生感知效应中的因果关系的客观测量。这些实验的结果将限制神经元和计算模型的时间处理。时间缺陷与正常衰老引起的变化以及包括阅读障碍、多动症、帕金森氏病、抑郁症和精神分裂症在内的疾病有关。一个更好的关于大脑如何编码时间的模型有可能增强对这些时间缺陷的理解，并可能对潜在的临床或心理干预产生影响。